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Polymer and ionic liquid (IL) mixtures have attracted an increasing amount of attention due to their unique properties and potential applications. The interactions between poly(ethylene oxide) (PEO) and imidazolium ILs of different cation alkyl lengths and anion structures have been investigated by measuring melting points (Tm), contact angles, and rheological properties. Tm of crystalline PEO dramatically decreased when it was blended with ILs. Similarly, the contact angles of different ILs on a PEO surface proportionally decreased. The interaction energy, as calculated from melting point depression using the Flory equation, increased with the length of imidazolium alkyl cations and the size of anions. The different anionic structures had a more significant influence on the interaction energy than the alkyl chain lengths of cations. These trends accorded with the solubility obtained by high-energy X-ray diffraction and swelling ratio measurements of PEO in different ILs [Asai Macromolecules 2013, 46, 236...

A ZnO/TiO 2 composite layer was fabricated on top of a nanoporous TiO 2 layer to form a heterostructure bilayer photoanode (P-PZ). The in-situ scattering sites of ZnO were formed inside the assembled photoanode (P-PZ) through the dissolution of ZnO particles caused by soaking in titanium tetrachloride solution. In comparison, the conventional TiO 2 photoanodes (2P) and photoanodes with incorporation of the commercial large TiO 2 particles (P-PT) were also prepared, and the three photoanodes (2P, P-PT, P-PZ) were all with the thickness of about 14.2 μm. A light-to-electricity conversion efficiency ( η ) of 7.50% was received for the P-PZ-based DSSCs, much higher than that of the DSSCs with 2P (5.34%) and P-PT (5.96%) photoanodes. The superior performance of the DSSC with P-PZ photoanode is mainly attributed to the following factors. (i) The in-situ scattering sites exhibit great light scattering ability, resulting in the great improvement in the short-circuit current density ( J sc ). (ii) The ZnO-coated TiO 2 structure shifts the conduction band of TiO 2 , leading to the great increase in the open circuit voltage ( V oc ).

Cellulose triacetate (CTA)/xanthated cotton fiber (XCF) blend ultrafiltration (UF) membranes were prepared via phase inversion in the absence and presence of 2.5 wt.% additive, namely polyethylene glycol 6000 (PEG 6000). The XCF which can adsorb heavy metal ions was chosen as the modifier. The prepared membranes were characterized using pure water flux, contact angle, rejection of the metal ion solution, flux recovery ratio, and mechanical analysis techniques to investigate the influence of XCF and PEG 6000 on the final properties of the membranes. Membrane cross-sectional structures and surface morphology were characterized by scanning electron microscopy and atomic force microscopy, respectively. The results showed that the permeability, ion adsorption, surface hydrophilicity, and mechanical properties of the ultrafiltration membranes were enhanced greatly. According to molecular weight, the interception rate of heavy metal ions followed this order: Cu(II) > Zn(II) > Ni(II) > Cd(II). Compared wi...

A well-defined azido-poly(N-isopropylacrylamide) (PNIPA) was prepared by reversible addition-fragmentation chain transfer polymerization of NIPA and glycidyl methacrylate followed by the azidization of pendant epoxyl groups. Then the polymer was crosslinked via Click chemistry by bis- or tetra-alkynyl terminated compounds, which were synthesized through esterification of 1,3-propanediol and pentaerythritol with propiolic acid and 6-heptynoic acid, to fabricate PNIPA hydrogels. And the swelling properties of obtained hydrogels were studied as functions of crosslinker dosage and species. The results showed that the decrease of crosslinker dosage or increase of chain length thereof could enhance swelling capacities of hydrogels due to bigger free volumes within networks; the functionality of crosslinkers almost had no influence on swelling properties of hydrogels. In addition, no obvious distinction was found for lower critical solution temperature and swelling response to a temperature jump during reswellin...

Cellulose triacetate (CTA) ultrafiltration membranes were prepared via phase inversion technique using hydrophilic TEMPO-oxidized cellulose nanofibrils (TOCNs) as modifying agents. The permeation performance of the prepared membranes was evaluated in terms of pure water flux (Ji), protein rejection (Rm) and flux recovery ratio (FRR). Membrane surface morphology and cross-sectional structures were characterized by atomic-force microscopy (AFM) and scanning electron microscopy (SEM), respectively. XRD was performed in order to investigate the interactions between membrane components. Meanwhile, the effects of TOCN concentration on hydrophilicity of the membrane surface and mechanical properties were also examined. The experimental results indicated that CTA/TOCN composite membranes exhibit significant differences in surface properties and intrinsic properties due to the addition of TOCNs.

Cellulose aerogel materials were prepared by combining dissolving cellulose in an ionic liquid, 1-allyl-3- methylimidazolium chloride (AmimCl), and drying in supercritical CO2. The rheological properties of the cellulose solutions of different concentrations and their gels regenerated in different coagulation baths were studied. The porous structure and morphology of cellulose aerogels were found to be affected by cellulose concentration and nature of the coagulation bath. With increasing initial cellulose concentration, the porous structure of cellulose aerogels became more dense and uniform, leading to the gradual decrease of the specific surface area. Further, it was also observed that, both viscosity and the polarity of coagulation bath affected the structure of cellulose aerogels. High specific surface area cellulose aerogel materials could be prepared by controlling the experimental conditions. The obtained cellulose aerogels had relatively high char yield at elevated temperature, which makes them potential precursors for fabrication of novel mesoporous carbon materials.

Taking advantage of the negligible vapor pressure and dissolving features of ionic liquids (ILs), the solution morphology and dissolution process of cellulose in ILs have been visualized directly by conventional transmission electron microscopy (TEM) at room temperature for the first time.